Professor Don Fuller managed Francis Xavier's election campaign last year, leading him to a 16 per cent swing and narrow win in the seat of Arafura.

He told 105.7 Breakfast he has since left the party after unexpected price hikes in Power and Water tariffs and a failed bid to continue working with Mr Xavier after the election.

Professor Fuller proposed to continue working alongside Mr Xavier to assist the first-time politician into the business of Government - a request Mr Xavier and a Tiwi Elder had made.

"It became clear to me and Francis that he was going to need help with the intricacies of Government," Professor Fuller said.

"This was no career move for me - it was going to be challenging and rewarding at my age and I am an old fart," he said, adding he even offered to reduce his salary by half.

Soon after the election win, Mr Xavier came under attack from the Opposition for promising voters he would push to reintroduce full-strength beer on the Tiwi Islands - something Chief Minister Terry Mills denies having endorsed.

Mr Xavier told ABC News at the time he wanted Tiwi Islanders to have access to alcohol in their communities, rather than travelling to Darwin and spending money there.

"They (Tiwi Islanders) see resources being taken from them to go very rapidly to the mainstream, even though the election was actually won in the bush," Professor Fuller said.

Speaking at a recent protest rally at Parliament House opposing a 30 per cent hike in power prices, Professor Fuller said The Chief Minister had failed on election promise to reduce the cost of living for Territorians.

"I do see the need for budget expenditure reductions but to do things so suddenly and so sharply without any consultation is the key issue a lot of us are taking issue with," he said.

"It's very important these strategies are implemented in a way people can deal with.

"Politics requires more than just digging in there...it requires an ability to negotiate, consult and unfortunately I don't think those signs are there."

He predicts the Chief Minister's leadership will come under challenge.

"I think there was a chance to really demonstrate leadership to bring people together and do things in consultation with the community... people have felt let down and felt deceived and therefore, they're angry."